SAT I 一日一问:2014年11月25日
The correct answer is C
Explanation
If Alan's package weighs p pounds and costs d dollars to ship, then 6 is less than or equal to p is less than or equal to 10. Subtracting 8 across these inequalities gives the equivalent (6 minus 8) is less than or equal to (p minus 8) is less than or equal to (10 minus 8), and so (negative 2) is less than or equal to (p minus 8) is less than or equal to 2. By the definition of absolute value, it follows that (absolute value of p minus 8) is less than or equal to 2 must be true.